DESCRIPTION: Total joint replacement is now commonplace in the United States. Approximately 600,000 joint replacements are performed annually, but they are sometimes complicated by joint loosening at the bone-joint interface. There is a greater incidence of alcohol-induced joint loosening. This presents a clinical problem for both physicians and patients. It is important to gain an understanding of the influence of alcohol at the bone joint interface in order to improve joint replacement outcomes for all patients. The research proposal is designed to facilitate understanding of alcohol influence at the bone-joint interface by establishing an in vitro model and a proposed mechanism through which the effects of alcohol influence osteoblast adhesion to orthopaedic biomaterials. These specific objectives are designed to accomplish these tasks. Specific Aim 1: To determine the effect of acute ethanol exposure at moderate and high concentrations on osteoblast adhesion to orthopaedic implant biomaterials. Specific Aim 2: To determine the effect of acute ethanol exposure at moderate and high concentrations on TGF-beta1 enhancement of osteoblast adhesion and PTH modulation of TGF-betal enhanced osteoblast adhesion.